This huge and ambitious first novel by Dan Sleigh, an Afrikaans writer, reinvents the lives of the first white settlers in the Cape of Good Hope, in the 17th century. These were Dutch officials serving the East India Company and it is to them, I am sometimes tempted to think, that much of the narrow, unforgiving hatred that marked later South African lives may be traced.

Of course, these figures were familiar to every schoolchild in white South Africa: men like Jan van Riebeeck and Simon van der Stel, whose names were on street corners and public monuments, whose faces were on banknotes. They were heroes who brought, we were told until it came out of our ears, civilisation to the Cape of Good Hope.

What a relief, then, to find that the gods of our beginnings, revisited in Islands, were neither nice nor heroic. They were chancers, explorers, failures, many of whom only came to the Cape because it was halfway to their real destination, the glorious East, where the serious loot was to be found.

It is somehow reassuring to know that the Dutch East India Company recruited as servants and sailors not the impeccable white paragons touted in the apartheid history books but the dregs of Dutch and German gutters. A clutch of brigands passing itself off as a master race which, when it wasn't being brutal and stupid, was numbingly dull. Nothing speaks more damagingly of later claims of white superiority than the tight, mean way it all began. Jan van Riebeeck, the first Governor, had not been in the Cape for more than two minutes, historically speaking, before he had built a fort against foreign enemies, followed it with a hedge to divide settlers and native tribes, and then added a castle to shut out the world - and thus set the political tone for centuries to come.

Islands is not really about parcels of land surrounded by sea (the title is taken from John Donne's poem), though it gives over much space to early settlement on Mauritius, as well as the uses to which Robben Island was put. The first settlers cultivated, and then betrayed, a Hottentot chief known to the English as Harry and to the Dutch as Herrie and whose real name was Autshumao. When they tired of him, they locked him up on the island.

Chief Harry's story is the strongest of the seven lives, or voices, that are woven together to make the novel. Harry has always been a vivid figure in South African folk-memory; he is so endearingly original, and his fate so sad. He was the first indigenous South African to help the pale invaders; the first to be suborned, plied with booze and tobacco; the first of many political prisoners, over the centuries, to be exiled on Robben Island.

A little girl from Harry's people, whom the Dutch settlers named Eva, was adopted by Van Riebeeck. Eva serves in the novel as a living link between the indigenous tribes of the Cape and the European settlers who will destroy them. Eva's marriage to a white ship's surgeon produces a daughter, Pieternella, who binds together the lives and deaths of the first people at the Cape, Dutch and Hottentot, much as it binds their descendants to this day. Pieternella is of mixed parentage; she is neither white nor brown, and so she is marooned on the island of her racial otherness.

Islands is a work of historical devotion. You have to admire its scope and energy, and its unsentimental readings of how South Africa got to be the way it is. The trouble is that the desire to rescue these lives from the distortions of apartheid historians is too earnest. Islands is long on meticulous reconstruction of times past - but short of the heartbeat that makes for life. Sleigh insists on telling us more than we want or need to know. The costumed storytellers merge into one another. In the end the longueurs make it hard to tell one voice from the next; worse, they deaden our capacity to care.